Pesticides or pesticidal methods, such as insecticides, are generally used to increase food production, decrease the amount of disease carrying pests, and limit human contact with such pests. Currently, the primary method of controlling such pests is through the application of pesticides containing synthetic chemical compounds. Not only are such chemicals becoming less effective at controlling and/or killing the pests, but they can also cause undesirable effects on both the environment and humans.
Initially many of the synthetic chemicals utilized as pesticides were very effective in controlling and/or killing the pests. However, after extensive usage the pests eventually build up a tolerance or resistance to some such chemicals. Once one chemical loses its utility, other synthetic chemicals, that the pests have not yet developed a tolerance for, are used. This cycle can result in a very large number of synthetic chemicals being released, largely unchecked, into the environment. The interaction of any synthetic chemical, let alone a number of such chemicals with the environment always comes with unexpected consequences.
The non-selective way in which synthetic chemicals control pests also makes them undesirable. The chemicals can often have unexpected and serious detrimental effects on desirable insects or animals as well as the pest insect or animal.
The chemicals can also contaminate areas in which humans have significant contact and cause serious effects on human health. Because of the large number of such synthetic chemicals in the environment, the interaction of such chemicals is inevitable. Often, the combined effect, often called the synergistic effect, of such chemicals can greatly outweigh their singular effects.
Furthermore, synthetic chemicals can often persist in the environment almost indefinitely. These concerns, and others, have lead the United States Environmental Protection Agency (EPA) to regulate and even ban a number of synthetic chemicals used as pesticides.
Because of the often detrimental effects of synthetic chemical pesticides and the EPA's regulatory ban of some such chemicals, a number of alternatives to synthetic chemical pesticides have been proposed and researched.
One such alternative is the use of biological organisms to control the undesired pests. Although this approach has had some significant advances and triumphs, concerns regarding the organism that is being released to control the pest will always remain. Another alternative that is seeing an increased level of interest, is the use of natural pesticides. Natural pesticides are compounds that exist in nature (e.g. in plants, animals, or other insects) and have properties that allow them to be used as is, combined, or modified to be used as pesticides.
An example of a natural pesticide is disclosed in U.S. Pat. No. 6,004,569 (Bessette et al.). Bessette et al. discloses a formulation and method to kill invertebrates, especially insects, arachnids and larvae. The disclosed formulation includes a chemical compound having a six membered carbon ring having substituted thereon at least one oxygenated functional group. Bessette further indicates the formulation is a chemical component of a plant essential oil.
U.S. Pat. No. 6,231,865 (Hsu et al.) is another example of a natural pesticide. Hsu et al. discloses a composition that includes garlic oil or extract with essential oils. The disclosed formulations are said to have a synergistic effect which significantly increases the known qualities of garlic oil.
Although natural pesticides have previously been utilized, there still remains a need for effective natural pesticides that do not have the undesirable effects often exhibited by synthetic chemical pesticides.